This lesson covers the concept of contact resistance, focusing on two types of resistance: streamline resistance and contact resistance. It explains how these resistances occur when two conductors are joined together, either through welding or using nuts and bolts. The lesson also discusses the distortion of the current path and how to minimize it by increasing the overlap portion between two conductors. It further delves into the concept of point contact and surface contact, and how to transition from one to the other to reduce resistance. The lesson also touches on the importance of voltage drops in conductors, the role of wiring harnesses in power delivery and monitoring, and the significance of maintaining equal resistance in multiple current paths. An example of designing a bus bar is also provided to illustrate these concepts.
00:19 - Contact resistance and streamline resistance
04:49 - Voltage drops in conductors
08:53 - Example problems of voltage drop and its solution
14:47 - Current equalization in parallel path and Example
18:57 - Different joining and welding methods
20:50 - Busbar joining methods/a>
22:06 - Standards and testing
23:04 - Summary of electrical design
- Streamline resistance and contact resistance occur when two conductors are joined and can be minimized by increasing the overlap between the conductors.
- Transitioning from point contact to surface contact can reduce resistance.
- Voltage drops in conductors are important to consider in power delivery and monitoring.
- Wiring harnesses play a crucial role in power delivery and monitoring.
- When dividing current into multiple paths, it's essential to maintain equal resistance in all paths.
- Designing a bus bar involves considering factors like current density, ventilation, manufacturability, cost-effectiveness, and resistance minimization.